Welcome to the new forum! We upgraded our forum software with a host of new boards, capabilities and features. It is also more secure. Jump in and join the conversation!
You can learn more about the upgrade and new features here.
You should be able to export them from BeerSmith 2 to a BSMX file, then open that in BeerSmith 3 and copy/paste them over to your Styles profile table. You probably need to go into Options->Brewing first and set it to display all style guides.
However in some ways this may work better with BeerSmith 3 which lets you select multiple style guides to display where BeerSmith 2 only allowed one at a time.